CN104428629B

CN104428629B - Optical position transmitter with analog memory unit

Info

Publication number: CN104428629B
Application number: CN201380035690.8A
Authority: CN
Inventors: R·菲尔施
Original assignee: Hexagon Technology Center GmbH
Current assignee: Hexagon Technology Center GmbH
Priority date: 2012-07-04
Filing date: 2013-07-04
Publication date: 2017-12-05
Anticipated expiration: 2033-07-04
Also published as: WO2014006147A1; EP2870433A1; US20150144774A1; CN104428629A; US9482560B2; EP2870433B1

Abstract

The present invention relates to a kind of position coder, the position coder has：Position code and at least one of optical sensor element for detecting the position code.The sensor element has the row of photosensitive detection zone, and incident photon is converted into electric charge by it；And reading out structure, it is used to export the electric data-signal corresponding to stored charge.The sensor element has：Analog memory cellular construction, it is N to have quantity>The non-photosensitivity analog memory unit of 1, with interim storage electric charge；And electric switching construction, by the electric switching construction, can between detection zone and memory cell, charge transfer is carried out between memory cell and between memory and sense line.

Description

Optical position transmitter with analog memory unit

Technical field

Member is obtained the present invention relates to the analog memory including the sensor element with analog memory and by photosensitive The line of part carrys out at least one of method that optics obtains position code.

Background technology

In particular it relates to position coder technical field, wherein, for the purpose for determining position, pass through biography Sensor component obtains position code, such as in the various applications for determining length and/or angle along one or more dimensions It is middle to use.Some illustrative embodiments are for example in US 5,402,582, EP 1 474 650, US 7,051,450 or US Found in 7,069,664, wherein, the sensor element described in the present invention applies also for having the position of different designs to compile The embodiment of code device, wherein, it is determined that in the range of position, execution position or location code (or at least the one of this code Part) optics obtain.

Become known for obtain position code very different method, for example, imaging, shadow-casting, projection, reflection, do Relate to pattern formation, the outside or inside illumination of code, automatic luminous or fluorescent code pattern etc..Electromagnetic wave, specifically, optics Electromagnetic radiation in wave-length coverage is preferably used for non-contact transmission of the code pattern to sensor element.In such case Under, the code can be realized by incremental manner, absolute mode or by mixed form, for example, in the only a part of measurement range It is interior definitely or, the increment in absolute coding area.For example can be in WO 2008/019855, WO 2010/ for its example 139964th, found in DE 11 2,006 003 663 or WO 2004/094957.

In general, in this case, by obtaining position generation including multiple active sensor elements for obtaining area At least a portion of code.These, which are obtained, distinguishes the liftoff subregion for obtaining the code section.The acquisition area may be implemented as point From unitary part, it for example by row or by two-dimensional matrix is arranged on private location.The acquisition area (pixel) is herein by company It is continuous, substantially uninterrupted to arrange to go here and there together, i.e. the continuous or quasi-continuous arrangement as photosensitive area.Here, the accurate of photosensitive area connects Continuous arrangement is to go here and there together while only have therebetween small space (compared with their own active sensor area), for example, It is common in the case of known ccd line sensor or CCD face sensor.

However, the arrangement of photosensitive area can also be realized by continuation mode, i.e. it is not spaced between pixel, wherein, collision two The photon of intermediate region between individual pixel gives one or the other pixel with a certain probability assignments.Obtain the geometrical arrangements in area also The code to be obtained can be particularly adapted to, or it can be therefore shielded, for example, by according to the code pattern to be obtained The sensor of setting, or by covering the acquisition area, so that its sensitivity is restricted to wish surface district.Thus, except most Beyond common linear arrangement, obtaining the geometrical arrangements of element can also bend certainly.By example, the row or square of element are obtained Array element part could be arranged to line or rectangle, and use arc form, proportionately angular way or have any curve form, or Person is globally etc..

At least a portion of the code is in the case of position measurement, the situation especially in high precision position measurement Under, obtained on schedule by sensor element.High position accuracy can be achieved, especially by with sub-pixel point Code section acquired in resolution estimation.In addition to achievable position resolution when obtaining the code, accurately set and obtain Take the achievable degree of accuracy that the time in this case can also be on the measuring system operated using it to have to significantly affect, especially It is if then linked each other by multiple position sensors multiple physical dimensions of acquisition and these sizes, for example, for true The multi-dimensional position of earnest body.The precise time of position acquisition comes in the case of being measured in the mobile period of object to be measured Say, i.e. in the case of the position changed over time and important.Especially in the case of high position resolution, Even for example, about several microns or second of arc higher resolution, minimum movement (such as example because vibrating, vibrating, the chatter of user) It can be obtained by position coder.

Therefore, measured value is obtained generally by means of trigger signal to trigger, and which defines the hope time for obtaining positional value. By example, a flank of electric signal can be used to trigger measured value acquisition.In managing in this place, it can apply and be based on event Triggering, for the situation, the measurement is triggered by external event.Can also be by internal or external clock come using tactile Hair, it is alternatively synchronized on multiple sensors.By example, in such a case, it is possible to perform from it is multiple (and Spatially it is distributed) the synchronous determination of the positional value of position coder, and its measurement data can then link, with according to it Determine hyperspace place.It it may also be desirable to read actual value signal (by small Jitter institute from position coder circulation Disturb), for example, for the actual value signal in the time domain discrete regulation of positioning unit.Another example of particular implementation Such as it is described in EP 2533022.

The application example for needing the position of pinpoint accuracy to determine includes measurement apparatus (for example, geodetic instrument or coordinate are surveyed Amount machine).Equally in the case of special purpose machine tool (for example, pick and place machine, laser cutting machine, grinding machine, lathe, milling machine etc.), for position Put accuracy of measurement and express very high demand.In managing in this place, determine that position specifically can be by linear position, rotation position Put or it is combined to be formed.High synchro measure value obtain may also monitor and diagnostic system in need, such as acting on one's own In profit application PCT/EP2012/054095 system.

In the position sensor of prior art, the illumination condition of sensor element is obtained when there is trigger signal, is connect , the illumination condition is exported (generally only by single channel serially) with pressing clock pixel-by-pixel.Only in all pixels When clock exports, the further triggering according to trigger signal can be continued, and current code area is obtained by sensor element. Therefore, only can newly be measured again when reading baseline measurement completely.

Because this of CCD chip sequentially reads the time quantum for needing to can not ignore, achievable read-out speed leads to It is often at a fairly low, so as to also there is minimum limitation for the time between the acquisition that two are recurred.This be it is real, Especially, if except CCD pixel-by-pixel by clock output in addition to, also each absorption value is simulated to numeral change, It may equally take.Changed by so-called " pipeline system " A/D of application, during at least digitized conversion time is managed in this place Avoided completely even being reduced, in addition to the residual delay time.The maximum for pressing this sensor of clock export-restriction can be real Speed is now measured, the duration is may be allowed so as to have an effect on the minimum between two trigger events, during this period, can obtain completely Take two values of the illumination condition, and position code value thus.Although for actually in position existing for the triggered time Approaching for measured value can be obtained herein by the interpolation between two or more measurements in time domain or extrapolation, so And the actual acquisition of the measured value in the triggered time is impossible.

Such as the solution for being used to increase read-out speed known from US 4330796 or US 2012/081590 is So-called framing (framing), wherein, always whole CCD structures are not by reading and only (it is also known as its currently associated part ROI (abbreviation in " concern area ") is read；This is possible under corresponding shorter amount of time.Reducing readout time can be with (for compromising position resolution) is obtained by binning (binning), wherein, the technology is generally intended for use primarily in increase Luminous sensitivity, in the case of position coder for, it generally has secondary importance, even because what is well limited is adjustable The lighting condition of section is generally universal in position coder, wherein artificial light and relevant with exterior light influence close be present Seal outer cover.For in the case of the position coder of this encapsulation, such as it can also be obtained by the appropriate actuating of light source Spectrum assignment, especially by the photoemissive intensity of regulation and/or lighting time interval.By example, on sensor element The local smearing (smearing) of code image can be by means of illuminating (for example, using nano-seconds or shorter in short term Flash of light form) avoid or reduce, it is probably important, especially in the case of dynamic mobile.

The line sensor or face sensor used in the prior art includes analog interface or digital interface.By showing Example, has light sensitive pixels line, incident photon is converted into electric charge by it according to the simulated optical sensor element of CCD principles.According to The design of semiconductor structure, these can be implemented as front side-illuminated CCD or back side illumination CCD.These electric charges press so-called potential well Collect in the semiconductor structure, and be then displaced to output section (=by clock output) as charge simulation, wherein, it is each single The collected electric charge of pixel is continuously converted into the voltage proportional to the quantity of electric charge, or is converted into relative with carrier quantity The digital value answered.It is this to be exported by clock by the way that the potential well for wherein containing electric charge is shifted along outbound course, with linear displacement Buffer mode (also known as bucket brigade (bucket brigade)) is carried out, on the other hand, various technologies are known (examples Such as, two-phase, three-phase or four phases are exported by clock).

In order to reduce halo effect and/or smearing, it is known that CCD according to transfer principle between frame or line or according to this two The combination of kind of principle operates.In these, electric charge is passed to dimmed semiconductor region after the time for exposure is limited, then from Wherein read.

By example, in the case of television camera for, face CCD chip is known, wherein, from photosensitive area The displacement of electric charge occurs in non-photosensitive components area (for example, the component area covered by optically opaque mode), and it is compiled in even number Performed on the second side in the case of odd-numbered line on the first side in the case of number line.Both sides are divided to as this Result, can by individually read even lines or odd lines be advantageously employed wire jumper (line-jump) method read video Image, for example, as described in US 7315329.

In slow motion technology, so-called high-speed camera operates also according to similar principles, by means of it, obtains each second The frame recording speed of a large amount of frames, for example, as described in US 2003/0058355.In these, photon charge inducing Sequentially be displaced to it is multiple it is different transmit detectors, then in all cases independently to the time-consuming reading of its application (and Digitlization) processing, i.e. it can be said that concurrently applying.Required high frame rate can be realized by the plurality of parallel read-out, make For as a result, the limitation of the readout time from single image can be avoided.However, this is with having a disadvantage that, i.e. it is needed More times of chip areas corresponding to wanting, for transmitting array and multiple output stages.

In addition to CCD technologies, light sensor can also realize digital interface, for example, as utilized CMOS skills The sensor of art.Here, correspondingly, an estimating circuit can be distributed to each acquisition area of the sensor, estimation electricity Road internally analogs to digital conversion for each element sensor, buffers the digital information and provides it for reading Go out.Here, buffer by means of the digital storage for digital value and occur.Although it can avoid being used for by parallel read-out The time of every single line is serially exported by clock, but for converting the charge to voltage signal and being converted into digital letter forward Number time, and the time for sequentially reading digital value still suffer from, and limit maximum possible triggering speed, it is specific come Say, particularly if the conversion does not pipeline completely.

The method relevant with sensor also be present, the advantages of it attempts unified ccd sensor and cmos sensor, for example, " in ELECTRONICS LETTERS " volume 44 8 (date is on March 10th, 2008), P.R.Rao, X.Wang and A.J.P.Theuwissen " CCD structures implemented in standard 0.18mm CMOS Described in technology ".However, the complex fabrication process needed for the technique is only grasped by the considerably less producer, and The advantages of can thus obtaining generally can not to during generation increased process complexity make explanations.

The content of the invention

It is an object of the invention to improve position coder, the especially position coder including optical sensor element, Specifically, its high precision compared with time of measuring and position resolution.

For in the case of the trigger signal for being wherein used for measured value acquisition quickly continuously follows each other, specific purposes exist In the behavior for improving position coder.

Alternatively express, a purpose of the invention is to provide a kind of position coder, and the position coder includes using In the optical sensor element for obtaining position code, wherein, the time that position code obtains can be very smart according to trigger signal Really set, and by means of it, for situation about quickly being followed each other even for multiple trigger signals, the position code is still Each that can be directed in these triggered times is kept individually to obtain.

Moreover, one purpose is to provide the favourable of the optical sensor element for the position code acquisition based on triggering Actuating.

The large-scale industrial production of the position coder and miniaturization and cost reduction are another part of the purpose.

Here, there is provided for the Code obtaining element of high precision position sensor, (it causes in short time frame Realize the Code obtaining based on triggering) and another object of the present invention, wherein, specifically, there is provided Code obtaining element Correspond to actuating method and associate the continuous part that actuating structure is also the purpose.

These purposes are realized by realizing the characteristic features of dependent claim.By the exploitation of alternative or advantageous manner The feature of the present invention can collect according to Patents claims.

Below, the present invention will illustrate in the embodiment of one dimensional line sensor.However, those skilled in the art are clear Chu, the present invention can also be applied to the position coder equipped with multiple photosensitive point sensors in a similar manner, and it is not pressed At least approximate continuous straight line (i.e., it is necessary to form a continuous lines) for obtaining area is set.

Position code is included and for obtaining at least one of of the position code according to the position coder of the present invention Optical sensor element.Here, the sensor element has the line in photosensitive acquisition area, and incident photon is converted into electric charge by it, and Reading out structure, the reading out structure are used to export the electric data-signal corresponding with stored electric charge.The reading out structure can perform By-line (=parallel) or element connect element (=serial) readout process.

According to the present invention, for the sensor element for the purpose of interim storage electric charge, including analog memory structure should It is N that analog memory structure, which has quantity,>1, the line of the insensitive analog memory unit of light, and electric switching construction, by Yu Qi, charge transfer can be performed between area, memory cell and sense line obtaining.Specifically, in this case, obtain The charge transfer between area, memory and reading out structure is taken with by-line to carry out.

Alternatively express, the present invention relates to the position coder with light sensor arrays, and it can be with simulation Multiple values of illumination condition in mode and in extremely rapid succession buffer sensor, so as to can be performed in short period of time And multiple measurements are buffered, the measurement can only be read in the time later.Here, specifically, the reading duration can be with The short time interval being longer than between measurement.Here, the value of triggering acquisition illumination condition can be triggered by electric trigger signal.

The switching construction can be realized in such a way, i.e. obtain the time of position code and by electric charge from acquisition Block transitive to the time of memory construction can determine according to trigger signal, and the time of reading out structure output can according to The trigger signal asynchronous read output signal determines, i.e. independently of the time of the trigger signal.

The invention further relates to such position coder, i.e. the sensor element for interim storage electric charge is implemented as Analog memory structure, it is N that it, which has the quantity of the insensitive analog memory unit of light,>The line of 1.Here, memory cell The quantity of line be more than the quantity for obtaining area, specifically, the quantity of the line of memory cell is obtains the multiple of the quantity in area. Here, the sensor element includes electric switching construction, by means of it, can obtain area, memory cell and reading out structure Between perform charge transfer, and it is realized in such a way, i.e. the charge transfer between the line of memory cell can be directed to Single line in memory construction or the subset execution for these lines.Specifically, in this case, memory construction In the top of line can be shifted independently of the bottom of the line of the memory construction.

Here, the embodiment of the position coder can include：The photosensitive single line for obtaining area, single read are tied Structure, and at least N >=2 of memory cell, specifically, N >=4 bar line.

Here, the switching construction causes the transmission that electric charge can be performed between following

Between obtaining one in the line in area and the line of analog memory unit, by according to the predetermined acquisition of trigger signal Time, and

Between the line of analog memory unit, specifically, wherein, the transmission can individually or optionally pin (son can be limited as one to each in these lines in memory construction or for the suitable subset of these a plurality of lines Collection) actuating, and

Between the line of analog memory unit at least one and reading out structure, according to for reading in the association triggered time The read output signal of the position code of acquisition.

Here, at least one second obtain thus to obtain first and first read with completing first the associating for acquisition Between perform, this second obtain electric charge be temporarily stored in an analog fashion in memory construction, and its can first read After going out, the time later in being read by least second reads.Therefore, the second triggering just may be used before the first reading is completed With.The result invented as application according to analog memory, very quick continuous multiple triggerings can be carried out (assuming that storage Device structure includes free storage line), it is independently of the reading duration.

The sensor element can include discharging structure, and it is realized in such a way, i.e. may be present in analog memory The electric charge in one in unit is discharged before charge transfer is into these memory cells.Here, the discharging structure is not It is wired to be applicable only to institute, and particularly, the son for the line that the quantity for being selectively used for analog memory structure is N Collection, it is applied particularly to the single line of memory construction.

The memory construction or its actuating logic unit can include memory manager, and it is based on trigger signal and reading Signal controls charge transfer.Here, the memory manager can be realized in such a way, i.e., based on read output signal, hair Transmit the electric charge in memory construction, and the output for passing through reading out structure in the raw direction based on analog memory value along reading out structure Data-signal.Meanwhile the memory manager can be realized in such a way, i.e., based on trigger signal, enter to be about to electric charge from Block transitive (that is, shifting) is obtained into memory construction.Specifically, the displacement can be implemented to it is in memory construction, Closest in the line of reading out structure positioning, and the electric charge wherein previously triggered is not yet stored.Therefore, the memory construction is pressed Such mode is realized, i.e. not only global memory structure can by-line displacement, moreover, the only a part or list of memory construction Individual line can be shifted by optional mode.Here, the two functions of memory manager can perform (except trivial independently of one another Beyond thing), i.e. specifically, the output can be relative to the triggering asynchronous implement.

The sensor element can be provided with the CCD with CMOS on common semiconductor substrate.Here, specifically, Wherein, the memory construction can use CCD technologies to realize, and the reading out structure can use CMOS technology to realize.

The sensor element can utilize correlated-double-sampling structure (CDS) structure to realize.Specifically, this can be subject to reality It is existing, in memory construction, the line (or reading out structure is in itself) that is delivered to from its realization in reading out structure.

At least one dark pixel can be included by obtaining the line in area, and it is protected from incident photon, and wherein, without because Electric charge caused by photon.The electric charge (specifically, spurious charge) of the dark pixel also passes as dark benchmark during by-line transmission Pass.The dark benchmark can be used to improve measurement signal, specifically, in the range of foregoing CDS.

In addition to the first step, by means of it, the biography can be realized relevantly with the triggering demand in position coder The improvement of sensor.It is above-mentioned according to sensor of the invention and its actuating except using above-mentioned form application in addition to, still also another The relevant signal instruction aspect that can obtain is improved in the range of one step.Even if without exploitation described below, above-mentioned basis Sensor of the invention can also be applied in numerous applications, and it can be viewed as independent invention anyway, but it can enter One step optimizes, as described in following development and implementation mode.

Especially, the result as the actuating based on triggering according to the present invention, in the case of no triggering, leakage electricity Lotus (for example, be thermally generated electronics ...) can be collected during the relatively long period and (previously obtaining light in analog memory In memory used in electric charge and unused memory in), the electric charge with the photon charge inducing actually to be read and Accumulation, and negatively affect or distort estimated result.Moreover, as being lacked based on external asynchronous triggering in the case of obtaining Weary displacement fixed cycles time and the result of sense line, the corresponding universal conditions before each reading are no longer required identical, Such as it is particularly the case for constant read-out speed.By example, and between the relatively long time between two triggerings Every the situation of trigger signal compare, generate seldom hot charge between quick two triggerings continuously followed each other.Existing In terms of the fixed frame rate of reading applied in technology, the condition in sensor actually continuously read for two it is identical, As a result, for example, average dark value can be subtracted each other with measured value, or other types of equalization can be applied, to improve letter Number quality and reduce noise.

Strategies as resetting memory and appropriate actuation, suitable for these discoveries are reset for memory cell The result of structure, other improvement according to the present invention can be obtained herein.

Thus, for example, empty or unused memory unit (it does not include any reading optical charge) can be by being put Electricity, the spurious charge that may collect wherein and be reset to what is limited completely respectively before optical charge therein is shifted Value.

By example, this replacement, which can rely on always to have, is directed to discharge channel (remover, discharging slot (gutter)) The unused memory unit of potential drop carry out, it only raises before by charge transfer into corresponding units.Therefore, pin The suitable reconfiguration structure (therefore it is activated by actuation circuit) of memory can be set in the semiconductors.

Alternatively or additionally, one or more dark pixels can also be common together with optical charge in all cases With displacement.The electric charge collected in the dark pixel can be used as a reference value for being secretly worth during estimation, and for example, with Measured value subtracts each other；This corresponds to the principle of correlated-double-sampling.

In addition to hardware optimizations, numerical value improve can also for example by determine sensor temperature, and based on itself and Photon generation and its time between reading based on electric charge statistically calculate the heat generation of desired electric charge to obtain, its Numerical model based on semiconductor, then, numerically the heat generation of electric charge can be compensated in the range of estimation.

, can also be in memory for those charge discharges that will be generated between two trigger events by incident photon It is middle that charge discharge will previously be collected by it in triggering using so-called rubbish line (trash line), during so as to by triggering Between obtain for measured value photronic finite-state.Only after exposure period, the actual electric charge that measures is displaced to down for it In one memory lines.Here, during reading, the memory lines with measured value are only read；Electric charge in rubbish line need not It must read, but can directly be abolished in the case of unread.In the case where relatively long time lacks trigger signal, In order to avoid electric charge from illumination photocell spill into other chip regions, so-called spill and leakage can be set, its when obtaining saturation, Released load by aiming mode before these electric charges bring the risk undesirably spilt into adjacent pixel or memory cell Stream, is similarly to the known smearing avoided in photographic sensor.Thus although this rubbish line principle needs more The memory lines (it, which is not contributed to, determines the position) of big quantity, but this allows to apply the heterogeneous semiconductor junction being easily processed Structure.

Alternatively, application specific architecture (specifically, in the case of photronic) can be arranged for triggering thing of releasing Electric charge between part, the application specific architecture will (for example, downwards, i.e. along sense line direction) by first direction for example in triggering The charge displacement of determination is into memory construction.However, in the case of no triggering, the electric charge that would not want to is in a second direction Discharging structure is displaced to (for example, upwards).

, in one embodiment, (and can also be at least in first memory list from photocell by electric charge by example In member) directly discharge and can be performed during the time when not occurring trigger signal.As the appearance structure of trigger signal is with being somebody's turn to do Discharge relevant potential barrier, the potential barrier is kept up to time for exposure (it can also be designed by adjustable way), so as to collect photoelectricity Lotus.These optical charges are shifted by means of potential drop towards unused memory unit.After this, potential drop is successively from photocell Established to discharging structure.The optical charge shifts according to the seizure condition of analog memory structure towards reading out structure, i.e. according to it In which memory lines store acquired optical charge and wherein which is not shifted.Here, at least one dark pixel may be used also To be shifted jointly in each line, the dark pixel does not include optical charge, and only comprising collected spurious charge.By considering to be somebody's turn to do The charge value of dark pixel or the electric charge during estimation, many ghost effects as mentioned can be compensated at least in part, for example, Also described in such as US 2012/0081590 or other places.

The invention further relates to a kind of be used to obtain position code come optics by the line of photosensitive acquisition element at least one The method divided, wherein, methods described performs following steps：Obtained in area is obtained and converted photons are into electric charge, and read (being triggered by read output signal) electric data-signal corresponding with the electric charge is exported in structure.

According to the present invention, in this case, according to the triggering of trigger signal, the electric charge is displaced to storage from area is obtained In device structure, the memory construction has the N of analog memory unit>1 line, and tied in the charge simulation by means of reading Before structure output by the interim buffer-stored of these electric charges in the memory construction.

Here, the result as the buffer-stored, the acquisition can be specific next relative to the output asynchronous implement Say, controlled by two independent actuation signals.

By means of switching construction, methods described can perform following steps：- caused by trigger signal-by electric charge from The photosensitive line for obtaining area is displaced in one in the line of analog memory structure.Moreover, by means of the switching construction, institute The method of stating can perform following steps：- because caused by read output signal-by electric charge from institute's line in analog memory structure One is displaced in reading out structure, and exports electric data-signal from reading out structure.

Here, the displacement about trigger signal conditioning can be along the direction of sense line, with the line in memory construction Promote and realize together, those lines of electric charge acquired in especially in memory construction, buffer-stored.Knot as the propulsion Fruit, the switching construction are realized in such a way, i.e. the displacement in memory construction can be directed to the list in the memory construction Realize to individual line or line group selection, and other lines in memory construction unshift.Here, select more in memory construction The subset of bar line can also shift together for the purpose of propulsion, and other, and the line taken in memory construction is not Displacement.

This method can perform following steps：Single line or these lines in memory construction is transmitted with selectivity Before subset, by the interim buffer-stored of charge simulation in memory construction.Here, specifically, the line in memory construction Top can be shifted independently of the bottom of the line of the memory construction, wherein, it is described as the result of the buffer-stored Acquisition can be relative to the output asynchronous implement.

Here, the read output signal can ground relevant with trigger signal temporally independent mode control.Therefore, the two signals can By by asynchronous in a manner of relevant each other.

In a specially for carrying out mode, memory construction management can be by this method with specific reference to FIFO principle By-line shift register.During the management, specifically, this in selective erasing and shift memory structure can be performed The subset of a little lines.Specifically, can be in this selective erasing before by the score of charge displacement to memory construction The score.

In one embodiment, the method according to the invention can be according to the trigger signal, by from the electricity for obtaining area Lotus

■ discharges in discharging structure, or

■ is stored in analog memory structure.

Here, the electric charge in memory construction can be displaced to closest in the vacant line of reading out structure positioning.Come From the electric charge of light-line thus for example optionally along reading out structure direction by-line shift, until these have directly been promoted Untill the front of busy line (wherein having stored the electric charge in preceding acquisition).

Thus, in this process, the busy line of memory construction does not shift in the way of according to trigger signal.

According to the triggering of trigger signal, the method according to the invention can perform following steps：

For ■ by previous spurious charge of collecting from obtaining in the First Line that area is displaced in memory construction, it is used as no generation Code garbage information line, then,

■ obtains the photon for establishing position code, and

By acquired electric charge from obtaining in the second line that area is displaced in memory construction, it is used as with code letter ■ The measurement line of breath.

Specifically, the electric charge in the rubbish line can be passed in discharging structure for electric discharge, and is measured in line Electric charge can be passed in reading out structure for reading.

The invention further relates to a kind of computer program product with storage program code on a machine-readable medium, its Hard wire programmable logic controller (PLC) is implemented as, or it is the computer data signal realized by electromagnetic wave to send.Here, The program code performs the method according to the invention, specifically, wherein, the program code is according to the position encoded of the present invention Charge transfer actuating is performed in device.Specifically, this program code according to the present invention position coder estimation list Applied when being performed in member and/or in coupled estimating circuit.

Brief description of the drawings

Below, it is right by completely exemplary mode based on the specific illustrative embodiment schematically described in accompanying drawing The method according to the invention and the apparatus according to the invention are described in more detail, and also discuss the further excellent of the present invention Point.Here, institute's diagram is not construed as representing size.Specifically：

Fig. 1 shows the first embodiment of the position coder according to the present invention, and the position coder is included with more The optical sensor element of the line of bar analog memory unit；

Fig. 2 shows the second diagrammatic illustration of the embodiment of the position coder according to the present invention, the position coder bag Include the optical sensor element of the line with a plurality of analog memory unit；

Fig. 3 shows the 3rd embodiment of the position coder according to the present invention, and the position coder is included for single One photosensitive line has the sensor element of four exemplary simulated memory lines；

Fig. 4 shows that first for the progress signal transacting in the embodiment of the position coder according to the present invention is fixed Shi Tu；

Fig. 5 shows the diagrammatic illustration of the example triggers and readout process in the position coder according to the present invention；

Fig. 6 shows the second timing diagram of the signal transacting in the embodiment according to the position coder of the present invention；

Fig. 7 shows the block diagram of the embodiment of the position coder according to the present invention；

Fig. 8 shows the flow chart of the embodiment of the method for obtaining position code optically；

Fig. 9 shows the first illustrative embodiments of the position coder according to the present invention；

Figure 10 shows the second illustrative embodiments of the position coder according to the present invention；

Figure 11 shows the 3rd illustrative embodiments of the position coder according to the present invention；

Figure 12 shows that the first of position coder in coordinate measuring machine, according to the present invention applies example；

Figure 13 shows that the second of position coder in geodetic instrument, according to the present invention applies example；

Figure 14 a to Figure 14 e show the example as the measurement for the adjoint quick multiple trigger signals continuously followed, The 3rd of position coder in coordinate measuring machine, according to the present invention applies example；

Figure 15 shows the schematic illustration figure of the 4th embodiment of the position coder according to the present invention；

Figure 16 shows the schematic illustration figure of the 5th embodiment of the position coder according to the present invention；

Figure 17 shows the schematic illustration figure of the 6th embodiment of the position coder according to the present invention；And

Figure 18 shows the schematic illustration figure of the 7th embodiment of the position coder according to the present invention.

Embodiment

Fig. 1 shows the position coder 1 (herein based on line sensor to illustrate) according to the present invention, and it is optically Obtain at least a portion of position code 9.The position coder 9 thus can for example with it is imaged, shadow-casting, projection, Interference figure formed etc. form, obtained by optical sensor element, wherein, the coding for example can use check plot, Optics is formed through the form of area and optically opaque area, surface texture etc..The sensor element being included in includes light Quick acquisition area 10, its distribution memory construction 11 of warp-wise, the memory construction have per 16 a plurality of analog storage of light sensitive pixels The line 13 of device unit 14.Therefore, the line 13 of a plurality of non-photosensitivity analog memory 14 can be used for optical receiver line 10, the memory energy Enough store the free charge generated according to incident photon p in optical receiver 16.Pass through example, technically, this structure CCD technologies can be utilized or semiconductor subassembly is fabricated to using the CMOS with CCD structures.If the structure chi of memory 14 Degree is smaller compared with photosensitive area 16, then this enables receiving compact on a semiconductor substrate.

In one embodiment, the content of analog memory structure 11 in this case, can be along vertical in the figure Displacement in downward direction (is represented) with the symbol of arrow 30.The very simple embodiment of reading out structure 12 for example may be implemented as CCD lines with such structure, i.e. the structure is used to the electric charge serial type in the line being displaced to output circuit.Here, read Structure 12 can use sense line form to realize, its as the lower side line in the CCD structures, including horizontal shift function 31, By means of it, serial type reading, which stores pixel charge, to be performed in order, by means of the output circuit, obtain at output section Electric data-signal 22, the data-signal depend on the pixel carrier of respective numbers.The reading can also be performed concurrently completely, Or perform at least in part.

The switching construction 15 is used for the displacement for activating electric charge, and it is according to outer triggering signal 20 and according to read output signal 21 To coordinate.

Fig. 2 shows the somewhat more detailed of embodiment but still is schematical diagrammatic illustration.It is photosensitive when photon p is collided Pixel 16 generates electron-hole pair, wherein, free electron 7 is captured under potential well.Knot as electrode 47 (dotted line is painted) Fruit, the form of the potential well can change between solid line 45 and dotted line 46 (along the potential axle (pot-axis) of coordinate system 55 Direction), and thus, electric charge 7 can be by the appropriate actuating of grid 47 and the vertical displacement (vertical axis (vert- of coordinate system 55 Axis)), as shown in arrow 48.In this case, these potential wells are protected in order to avoid light radiation (for example, by mask 6), with Just prevent from generating further photoelectron.The photoelectron can be stored in the potential well, and this is why to be also known as analog storage The reason for device unit m1, m2, m3.(in other figures, label 14 is also generally independently used for memory list with its order Member).As put shown in 56, being arranged in position coder for describing at this is close to arrangement repeatedly each other, divides respectively to obtain The line in the photosensitive acquisition area 16 equipped with memory cell m1, m2, m3 (also being arranged using line).

Here, lower side line is implemented as reading out structure 12, and it is in the illustrated case horizontal shifting register (coordinate The trunnion axis (hor-axis) of system 55), by means of it, pixel electrode 7 can be towards the position pixel-by-pixel of charge voltage converter section 50 Move (arrow 49), to be converted into simulating electric data-signal 22a, it can use an analog to digital quantizer, in sensor internal Or sensor external be converted into digital electrical data signal 22d.

Being obtained according to trigger signal can be with constant rate of speed or because the external trigger occurred in any non-determined time is believed Number (any kind of), or triggered by both combinations.Especially in the case of aperiodicity triggering, with for example existing By it is outside it is primary into trigger signal in the case of occur, Tathagata is from being used for coordinate measuring machine, sensor, end switch or use In the detection termination in any other source of trigger signal, it is also possible to must be provided for wiping the special precautions of CCD structures.

For in the case of the imaging sensor from prior art, whole CCD chip utilizes weight in all cases Confidence number is wiped.However, in the implication of the present invention, wipe whole analog memory and be not suitable for all situations, because the simulation Memory can still include not yet estimative, the previous measured value for obtaining line.But, in order to ensuring in the scope of the invention Memory finite-state, need to be differently carried out resetting in this case.Appoint if analog memory structure does not include What measured value (for example, in the case where constant rate of speed measures, wherein, the time between two trigger signals, which is no longer than, reads institute Take time), then in all cases it is possible to wipe whole analog memory structure (which simplify the actuating of erasing, and conduct As a result, higher reliability can be obtained).

By example, only can be shifted downwards in the electric charge for not needing mode to collect that do not estimate, and can be direct Discharge there, as the alternative case (that is, not being fed to serial type estimation, but specifically, discharge in parallel) for reading.It is logical Example is crossed, the electric discharge can realize (or following the latter) in the bottom right in last memory lines, the last memory lines Alternatively it can read or wipe.

Alternatively, the electric discharge for the electric charge that do not estimate between two trigger signals in photoelectric cell 16 (for example, receive This electric charge of collection) it can also be discharged directly at the photoelectric cell, for example, edge " upward " direction.This leftmost side in fig. 2 It is upper to describe by another grid 40 that potential barrier is activated to discharge part 42 (discharging slot, removing diode).The latter makes along direction 41 Existing electronics 7 may be discharged before trigger signal so that finite-state before optical charge 7 is obtained in photocell 16 and gesture It is dominant in trap m1.

Within the scope of this invention, CDS (correlated-double-sampling) structure can also be applied, is related to the measured value to rely on A reference value under all situations reduces the noise introduced during reading, for example, such as in US4287441 or at it Illustrate in its document.Moreover, when application CDS estimations, it can also for example exempt accurately weighs before reading each time Put reading out structure.By example, in the case of different value determines for, otherwise (potentially) become if the read out circuit Saturation is obtained, then only resetting turns into required.Moreover, in the case of different estimations, although using CDS principles, may Only exist every pixel and once read and digitize (for most of pixels 16), with all cases in transmit pixel electricity The conventional CDS of sampled reference value is compared before and after lotus, and it considerably reduces readout time.

If realizing correlated-double-sampling (CDS), this can be realized in the line of lower side.Here, the electric charge currently exported It can also be stored in the capacitor of CDS circuits, rather than in the memory of CCD structures.Here, the signal of actuating unit can root The time that measurement signal is displaced in CDS is scheduled to according to external signal or by predetermined sequence.By example, in an embodiment party In formula, be displaced in CDS always can directly perform before output.In this case, measurement signal is after the measurement (such as Described in the figure for the reasons why simplifying) do not shift in lower side line (it is preserved for CDS now), and it is opposite It is displaced in line thereon.Only when the read output signal is performed CDS, measurement 0 (m0) be displaced in sense line and with After export.In managing in this place or hereafter, the content of shared memory lines disposed thereon is it is possible thereby to promote.

Can be one or more by means of such as equalizing, reading moreover, being thermally generated carrier (so-called " dark current ") The known treatment of individual dark pixel, cooling sensor etc. is compensated or reduced.It is (so-called " to sweep slowly as slow reading according to the present invention Retouch ") result, be equally applicable noise reduction.Because according to the present invention, the reading is no longer result in encoder and is obstructed for another One trigger signal, so relatively slow reading can also be applied.Therefore, reading speed is no longer limited by triggering speed, specifically For, it is assumed that enough free storage lines can be still obtained, are remained less than thus, it is supposed that short-term triggering speed is multiplied by readout time The quantity of memory lines.

Fig. 3 shows the active optics surface using the form of pickup wire 10, and is below, for until four surveys Analog storage portion 13a, 13b, 13c, 13d of amount structure.The optical charge generated in pickup wire can shift along direction 30 Into memory construction, and in the latter, by-line it can also shift in all cases.Such as symbolically in the figure , compared with optical active surface, the region for analog storage portion 13a, 13b, 13c, 13d can take up semiconductor substrate Different zones.Specifically, in terms of its geometric scale, memory cell, which can be less than, distributes to its photosensitive area.

In order to describe according to position coder of the invention, to may also rely on the direction specified to describe embodiments thereof. Here, it is horizontal and vertical, or the figure for being related to accordingly describe in all cases is marked upwards, downwards, to the left and to the right, and It is not construed as absolute.The geometrical arrangements of structure in particular semiconductor structure can certainly deviate as mentioned herein these " logic " direction, it is assumed that do not clearly stated herein for semiconductor structure arrangement.

This is related to position coder 1, and it includes the sensor element for optical position Code obtaining, including horizon light- Line 10 and it is made up of multiple horizontal analog memory line 13a, 13b, 13c, 13d (its interior exemplary approach is shown in which four) Vertical stratification, it can be activated by switching construction, with the single analog memory line 13a, 13b of selective vertical movement 30, Electric charge between 13c, 13d.

Lower side line is implemented as the reading out structure for concurrently or sequentially output charge (for example, being converted into electric data letter Number for further processing and position determine).

According to the triggering of trigger signal, by photogenerated electric charge from the vertical movement of light-line 10 (specifically, continuous/serial) Into vacant analog memory line 13a, 13b, 13c, the 13d positioned closest to sense line 10, and the line taken does not move Position.After readout process is completed, (that may be present) occupied analog memory line 13a, 13b, 13c, 13d, which is based on reading, to be believed A line is shifted number downward vertically into sense line, and reads (horizontal or vertical) there.Positioned at the occupied of more top Therefore line promotes after a line is read.

So as to, in order to obtain this displaceable property, the line of memory construction can individually or by group selection shift, Wherein, property separately can be shifted especially in the presence of the line in memory construction, wherein be selectively chosen, memory construction Top line region can be based on trigger signal and promote relative to photosensitive line to shift, it is and separated, memory construction Lower section line region can be shifted based on direction of the read output signal along sense line.Here, between top line region and lower section line region The position on border can change according to the occupied state of memory.Because according to the present invention, trigger signal and read output signal can be with those This relatively asynchronous appearance, so a part of result of memory construction can also asynchronous shift relative to each other.

In another embodiment for the sensor element of the position coder 1 according to the present invention, this can be relied on The standard two-dimensional surface C CD structures changed in such a way generate, i.e. single line 10 is photosensitive now, and all another Outer line is dimmed, i.e. is covered by light opaque layer.Because these maskings (and thus no longer photosensitive), now can be by line It is solely for by-line and charge accumulator can be shifted, realizes the embodiment of line sensor in the switching according to the appropriate actuating present invention Shown in the case of structure, the single line or a part during its enabled selectivity displacement institute is wired are rather than just entirely storing Device structure.Here, for from the line clock of the photosensitive shifting charge of line 10 because of trigger signal and caused by.It is in love in institute by example Under condition, can with the rising edge and drop edge of trigger signal, by optical charge from line 10 be displaced to concealed wire 13a, 13b, One in 13c, -13d, i.e. along the direction of sense line by charge displacement to the last still unappropriated memory lines before it 13a, 13b, 13c, 13d, however, shared memory lines do not shift jointly.

Fig. 4 shows describe on leveled time frame t, measurement (that is, optics obtains) and that line is read exemplary tactile Hair timing and duration.Each trigger signal T0, T1, T2 in the line of top, in-T3 triggering medium lines measurement (m0, M1, m2, m3), i.e. the electric charge of light-sensitive element 10 is displaced in analog memory 13a, 13b, 13c, 13d.In the subsequent time, These measurements can use analog form to be exported from shared analog memory 13a, 13b, 13c, 13d by clock, and for example Digitized using A/D converter, it is described in the line of lower section with association duration r0 and r1.There may be touching for top Hair and the signal (for example, electrical connection via sensor element) of reading for bottom.By example, acquisition or measurement can be with Using it is predetermined, specifically constant exposure duration m0, m1, m2, m3 is realized.In the First Line with memory value m0 After exporting at the end of the r0, then can (and thereafter directly) by be shifted down into reading out structure should Line is in next bar line of the time r1 outputs with memory value m1.

Alternatively, whole line or one portion can also be concurrently estimated in all cases using multiple A/D converters Point.Because as the result in the analog storage portion according to the present invention, reading speed is no longer and two direct continuous trigger signals The relevant key factor in allowed time interval between (for example, T0 and T1) (especially for depositing for memory construction 11 enough For the situation of reservoir depth), so for the interim of several trigger signal T0, T1, T2, T3 in extremely rapid succession following each other For the situation of burst, this parallelization and its hardware complexity are no longer compulsory during the reading for meet demand. However, reading speed should be clearly sized in such a way, i.e. the latter is enabled at least in equalization, average triggering speed All values are read in the case of rate, for its purpose, (at least in part) parallelization can also be applied to read when needed.Simulation The required depth (that is, how many line 13 needs to store in an analogue form, to meet the needs of the application) of memory construction 11 Also determined in the range of about the triggering and this consideration of read-out speed for the certain application cases.By example, In this case, the worst situation can be used, or can be with applied statistical method.

Fig. 5 is shown in which to generate finite-state before Code obtaining by ad hoc fashion the embodiment that solves.

In order to always have identical prerequisite in the position coder 1 for accurate measurement, it is advantageous to make active Involved analog memory area in sensor surface 10 and memory construction 11 enters finite-state, i.e. is touched for each Signalling T0, T1, T2, T3 are reset these (it is then also known as wiping).In the prior art, it is this in the case of CCD Erasing is always applied to total 11；However, as described above, in the present circumstance this not always can with because may The previous measurement obtained is still to store.

In order to realize these, rubbish line tr can be set in memory construction 11, and its buffer-stored may be first The electric charge collected in time between preceding measurement and current measurement.The unwanted electric charge (its produce between measurements (because Exposure, dark current etc.)) collect but be not estimated in these rubbish lines tr.Here, these rubbish lines tr can have and store Device line identical embodiment；Thus, specifically, the available memory only in structure 11 is used as rubbish line tr or is used as Memory lines m.

Rubbish line tr can be shifted downwards jointly with the line to be estimated in memory construction, and its electric charge can be direct Discharge part (for example, ground) is fed to, rather than is estimated.Otherwise this electric discharge can be directed to by exporting serial implementation by clock Whole line Parallel Implementation.Therefore, the only line comprising measurement data is exported and fed as data-signal to estimate.

Fig. 5 shows the example of this embodiment, and it has memory construction of the extension up to three lines compared with Fig. 3 11.Here, it is also expressly that ground depicts reading out structure 12.Thereunder depicting time progress (has and previous figure identical is determined When).Here, can also identify memory lines, to manage in this place in the single displacement that performs, with for memory construction, The lower section not shifted jointly in managing in this place has taken part and has promoted the electric charge just obtained.

Although measuring m0, output is r0 during m2 and m3 is measured, simulation linear memory is still occupied, until this Untill line all exports.Alternatively, the line is also possible to discharge after CDS, as an example, delaying by by electric charge Punching storage is in the capacitor for Serial output.The memory value only shifts downwards after r0 is exported, so as to wipe One rubbish line tr1.If (the being used as an alternative case as described above) line has discharged, the displacement of internal storage line is During r0 is exported caused by external signal, for example, equally, by means of it, triggering new measurement by means of another trigger signal m1.Then, the measurement signal for carrying out measurement m1 prepares output, and specifically, can directly export thereafter.Then, then Once displacement one, and rubbish line tr2 can be wiped downwards, and then, measurement m2 can be exported during r2 is read.

Alternatively, it is not desirable to have the electric discharge of scrap wire more can also be realized in memory toward Shangdi, as a result, Need less useless memory lines.Thus, for example, the useless memory lines specifically set can be arranged on light-sensitive element " top ", And therefore, measured value can be shifted down into analog memory array, and useless value can be with upward displacement.

In another embodiment, by the triggered time obtain two measured values between unnecessary electric charge electric discharge also Directly it can be realized on light-sensitive element, for example, the output being connected to the ground by it or the reference level under resting state, I.e., it is not necessary to trigger signal, and also carrier is only accumulated and is then shifted down into the case of triggering in the array. This principle has also been illustrated (for example, as removing diode) in fig. 2.

In this respect, timing diagram is again illustrated in Fig. 6, wherein, in the second line from bottom, it with the addition of For by the erasing grid d of the unnecessary charge discharge between measurement actuating.In this case, memory lines Propulsion is realized between two readout process r0 and r1 in all cases.

However, it is noted herein that in addition to photosensitive area, because (it may be distorted the electric charge from leakage current etc. Measured value) it can also accumulate wherein, so the line set for analog storage portion should be also wiped free of before these are write.Cause This, since bottom to top erasing should always no longer store measurement signal memory lines in, i.e. including from bottom to All empty store lines at top.Current measurement value is then shifted downward to the free line in lower side by these ceases to be busys.

Alternatively or additionally, it can also be considered by the common displacement dark pixel that is previously mentioned and during estimation To compensate spurious charge.

Fig. 7 shows the signal of the embodiment according to the present invention including optical sensor element position coder 1 Property block diagram.Here, according to position code 9, photon p collisions obtain area 10 and are converted into electric charge 7 wherein.These electric charges 7 are by logical Cross the mode of actuating logic 15a and switching construction 15b controls and be displaced to analog storage in the way of according to trigger signal 20 In device structure 11, and the there of electric charge storage in a memory cell, specifically, in CCD potential wells.Believe according to reading Numbers 21, electric charge 7 is displaced in reading out structure 12 by switching construction 15b, is risen therefrom, and they are being converted into electric data-signal 22 Under, by the time of association triggering 20, export as the defeated code word of the position code 9 acquired in.Here, actuating logic 15a is pressed Such mode coordinates the processing, i.e. and shared memory construction 11 promotes during reading along the direction of reading out structure 12, and And during triggering 20, the electric charge 7 in memory construction 11 is displaced in nearest free storage line 12 (such as from reading out structure See in 12), and manage do not shift institute's private memory structure 11 in device in this place.Here it is possible to before shifting each time Respective objects line is wiped, so as to the reception charge-trapping that may be present that discharges.

Fig. 8 is depicted for the exemplary process diagram for being used for optics and obtaining the method for position code according to the present invention.Should Method has two asynchronous components, i.e. the part that can be performed independently of one another in time domain-pass through the memory lines of limited quantity Away from slight causality condition and limitation.

Triggered by the trigger signal checked in inquiry 60 the part described in top half.The trigger signal it Afterwards, a line of memory construction is wiped in a step 61, and hereafter, the electric charge of light-line is displaced to wherein and with mould Plan form is stored therein.Optionally, the time for exposure to be defined such as before displacement, during the time for exposure, electricity is collected Lotus-be distributed in by code dependent mode on photocell.The electric charge can be further along the direction of reading out structure in memory knot Displacement is (as shown in step 65) in structure.After the corresponding previously erasing score that may describe in Figure 64, it is assumed that score Not yet it is previously stored shared by electric charge, it is checked by inquiry 63.

Triggered by the read output signal checked in inquiry 70 the part described in the latter half.It is false according to inquiry 71 If stored optical charge is present in memory construction, these are displaced in reading out structure in step 72, its when needed, Also it is wiped free of in advance.The displacement can be realized under application CDS principles, or CDS can be performed before displacement.Memory knot Remaining line (wherein, being equally stored with the optical charge from other triggered times) in structure therefore in step 73, along sense line Direction promote.In the sense line, read in step 74 and be converted into electric data-signal, the data-signal represents to press institute Associate triggered time, the lighting condition at light-line.Here, reading for output line can be with the mixed of serial or parallel or both Conjunction form is realized, and can also for example include the amplification and/or digitlization of the value.Reading 74 can be in time with propulsion 73 Or Parallel Implementation before, afterwards,.

Fig. 9 is shown according to the present invention as the rotation position with the annular code supporting body for carrying position code 9 The embodiment of the position coder 1 of encoder.In the left-hand parts of the image, pass through optical radiation p using reflective method Code is collided, and in right-hand sections application light transmission method.It is alternative which constitute two, its generally in a position coder not It is used together.Generally performed however, position code obtains by multiple points on code supporting body, will pass through equalization, miss Difference modeling etc. come improve accuracy of measurement or create redundancy.By example, code is rotated many times by being gathered along its circumference, It can also establish and compensate dynamic bias, as a result, for example, reducing the quality of the bearing for this rotary encoder Demand.

Figure 10 shows the printing opacity for being used for that position code 9 is obtained in the position coder 1 according to the present invention as described above Method.In addition to using the imaging of printing opacity and light tight surface district coding 9, different codes can also be used, for example, diffraction pattern Case or natural texture are as code

Figure 11 is shown according to illustrative embodiments of the position coder 1 of the present invention as linear position encoders In this example shown, using the transmitted illumination in position code portion 9, make a part for position code 9 can be by encoder 1 Optical radiation p obtain so that the line of light-sensitive element 10 can read the code area.Above, to according to the present invention's The embodiment of shown position coder 1 has been discussed in detail.

Figure 12 shows the example of the coordinate measuring machine 99 as joint arm, and it is equipped with touch-triggering probe 90.According to The linear and rotary position encoder 1 of the present invention is installed in shown joint arm, for the trigger signal according to touch probe 1 The high precision position value triggered obtains.Specifically, for the situation, the situation of operator's chatter that quickly move, or should And its situation of vibration, the trigger signal of measurement is triggered as extremely short time interval is (especially, as the prominent of trigger pulse Hair) occur.It can be obtained according to the position coder 1 of the present invention in the case of this burst trigger signal and be directed to individual pulse In the code word of each.

By example, can also be formed using the sensor to perform fast averaging.Thus, for example, in different implementations In mode, in the case of the joint arm with " touch-triggering probe " for, can trigger its measurement when in extremely rapid succession The measurement that line number amount is N is clicked through at one, the measurement then can in turn pass through while user aims at next measurement point Control unit 91 is more slowly handled.Formed according to the possible average value of the gained of N number of measured value and can aid in increase measurement The degree of accuracy contributes to debug to measure.

Figure 13 shows the geodetic instrument 98 with the position coder 1 according to the present invention, and it is used to measure by triggering When time determine the target collar of the instrument around the rotation position of vertical axis and sloping shaft.As can according to the present invention obtain High synchronousness result, can exclude to obtain movement in the horizontal direction and vertically between position, so as to that is, Be used in axle movement servomotor still vibrate or have more than its position, can also determine measured by space coordinates height one Cause property.

Figure 14 a show the exemplary application of position coder 1 in coordinate measuring machine 99, according to the present invention, specifically For, for establish caliber, have measurement termination 95 joint arm in.Here, the rotation from the joint arm and/or line The positional information of property editing machine 1 obtains in the case of each trigger signal.Here, the measurement usually relies on to be measured The user of the forked measurement termination 95 of the top of pipeline 94 guiding is performed with hand.However, alternatively, the movement can also pass through machine Moving axes measuring machine 99 is performed by automated manner.

Actual measure is carried out in such a way (as shown in Figure 14 a to Figure 14 e), i.e., trigger signal presses light beam 92nd, 93 triggered because of any time when test object 94 is interrupted or rebuild, trigger signal triggering determines angle and/or length Measured value.

There is no break beam 92,93 in Figure 14 a.If measurement fork 95 reduces above pipeline 94 now, dotted line is retouched The first light beam 93 painted is interrupted, so that the first trigger signal of triggering, this shows in Figure 14 b.Further sunk by pipeline 94 During being dipped into fork 95, the second light beam 92 (dotted line is described) is also interrupted, as shown in figure 14 c, so as to trigger the second triggering Signal.The triggering of 3rd trigger signal Figure 14 d show and because the first light beam 93 in light curtain is not prevented from and caused by.Scheming In 14e, the second light beam 92 eliminates again during further mobile above pipeline 94 of fork 95 to be stopped, is triggered the 4th and is touched Signal.

Now, can be in coordinate measuring machine 99 according in the position coder 1 of the present invention, during based on being triggered by this four times Between the measured value that triggers in all cases obtain to establish caliber.In the shown application of duct survey, the He of right-hand side side 93 The trigger signal of the sensor of left-hand side 92 is very quick continuous for example in the case where fork 95 moves between two parties above pipeline 94 Ground follows.As a result, accordingly, short measurement data is needed in the prior art, and it needs quick and generally also expensive electronics Device.Moreover, fast electronic device also generates high thermal losses, it, which is negatively affected, can obtain the degree of accuracy, such as because managing in this place The temperature change and coupled temperature expansion that period occurs.

According to the present invention, acquired position code is temporarily stored in position coder 1 height of itself in an analogue form now In fast-response probe (that is, for example, in CCD or CMOS array), it may be in short time interval and with low energy expenditure.With The information of analog form storage can then read-or even with slower speed.Thus, the reading can need anyway Longer period time between than two trigger signals.By example, (it for example links to the analogue value for the reading and processing Export, simulated to numeral conversion and position calculating by clock) can also be than the time flower between two triggerings of trigger signal Take longer.

Here, can also be parallel in addition to serially being exported by clock from value obtaining area, storing in an analogue form Digitlization, and can also alternatively by digital form, buffer-stored is on a sensor again.Moreover, acquired position code Direct estimation (or pretreatment in this aspect) can be realized on a sensor.

Figure 15 shows the embodiment with photosensitive line 10, for example, be embodied as backside illumination photodiode line, its with With simulation CCD storage organizations 11, wherein, the electric charge can be shifted along the direction of reading out structure 12 by direction of displacement.The displacement Triggered by trigger signal 20, and charge displacement is to vacant memory lines 13l lower side one.Occupied memory Line 13f is based on direction displacement of the read output signal 21 along reading out structure 121.In the embodiment described herein, this for example using CMOS technology with CCD structures and be embodied as the parallel estimation of whole line.

In Figure 16 embodiment, dark pixel 80 and then describe by photosensitive line 10, wherein, dark pixel does not collect photoelectricity Lotus, but spurious charge is only collected, it can then subtract each other with the measurement value as dark benchmark, specifically, read Period.In practical application, such as multiple this dark pixels 80 can also be applied, to obtain the average value that this is secretly worth.This is dark Value, which is subtracted each other, can perform (such as between the mid-term of reading out structure 12 is displaced to) in an analogue form, or be performed (i.e., by digital form After having been read).In the illustration, CDS circuits 81 are shown in reading out structure 12, and the CDS structures use dark picture The dark value of element 80.In this embodiment, erasing structure 82 is depicted on light-line 10, by means of the erasing structure, is being lacked In the case of weary trigger signal 20, by electric charge from photoelectricity tank discharge.Optical charge is only collected by the triggered time, and is then displaced to In memory construction 11, as previously described.The reading independently of trigger signal 20 come the read output signal triggered by can realize.Touch Hair 20 and triggering 21 are it is possible thereby to which asynchronous implement is (away from inappreciable condition, for example, such as impossible relative to each other Triggering is read before, at least one in memory lines must discharge during triggering, so as not to obtain data degradation etc.).

Figure 17 is implemented as the capacitor using CMOS technology rather than CCD structures exemplified with wherein analog memory structure 11 The embodiment of structure.Here, as in the case of CCD memories are simulated, the switching construction 85 of symbol instruction is set At each of memory lines, for 83 electric charges of by-line displacement 30 or erasing.Bottom side line is implemented as reading out structure 12, and it can By being activated in time domain independently of the read output signal 21 of triggering.

In other embodiments, rather than be embodied as the shift register using CCD technologies, simulation CCD memories it The reading out structure in (that is, its downstream along direction of displacement 30) is also implemented as capacitor line afterwards, wherein, electric charge is for estimating Count purpose and shift.These capacitors (can in all cases be pressed per one ADC of capacitor) or (passed through in order parallel Multiplexer circuit on one or more ADC) estimate.Therefore, CCD lines in bottom side are directed to during readout process and are followed by subsequent processing Release.

In this different embodiments, previously described correlated-double-sampling 81 can also by by electric charge from CCD structures Analog memory 11 be displaced in the capacitor of reading out structure 12 to apply.According to the realization, in this case, CDS 81 The parallel or serial execution of whole line can be directed to., can be with during digital pixel value is estimated in addition to simulating CDS 81 By then considering equally by digitlization and numerically (that is, such as subtracting each other), the execution of CDS at least one a reference value CDS digital variations.

In the embodiment shown in Figure 18, the reading out structure 12 for example may be implemented as the line of capacitor 86, and it sets Drop multiplexer architecture 87 is equipped with, as the data-signal 22 for amplification and/or the output section of A/D conversions.The reading is via one Or more read output signal 21 realize that it controls readout process.When starting each readout process, electric charge from simulation CCD The bottom side line of memory construction 11 applies to capacitor via CDS structures 81.Here, CDS 81 can be held parallel for whole line OK.Before electric charge is transmitted from CCD, capacitor 86 still can be by active erasure, i.e. for example by by charge discharge to lower electricity Gesture may spurious charge to discharge.

Here, simulate CCD memory constructions 11 to realize in such a way, i.e. the by-lines of optical charge p in a downwardly direction are moved Thus position can perform, wherein, specifically, not only whole memory structure 11 is displaceable, and is only shifted over until minimum Free storage line and untill the common displacement of line (its previously obtained optical charge take) further below.Moreover, Each in these lines is all individually wiped.In addition to single erasing, it can provide for wiping whole CCD structures 11 Appropriate actuating.The function passes through described switching construction 85 and represented from a line to next line or to ground come symbol.Here, Described switching construction 85 has symbolic sign, and need not describe the practice of the actual semiconductor structure for these functions Realize, these functions of being taken for themselves are certainly known to prior art.

Activate the displacement and erasing is realized by activating logic 15.The main purpose of the latter is, in trigger signal 20 In the case of, by by-line mode by the charge displacement in light-line 10 into CCD structures 11, and be displaced to minimum freedom there In line.Here, score or a plurality of score can be wiped before shifting each time.Read when according to the reading triggering of signal 21 During processing, electric charge (may be by using CDS) is displaced in reading out structure 12, and is exported therefrom, such as is exported to complete Pipeline ADC.In managing in this place, therefore all memory cells that optical charge is located at promote in a downwardly direction, wherein, target Line equally can accordingly be wiped in advance with the propulsion.This need the selectivity of CCD memory constructions 11 by-line shift and/or Function is wiped, it is not provided for example in regular frame transmits CCD.Here, trigger signal 20 and read output signal 21 can be only each other On the spot realize, specifically, by the asynchronous mode in time domain.

, can be with addition to above-mentioned FIFO principle (FIFO) using relatively more complicated connection and handover mechanism The memory lines are used as random access memory.By example, the electric charge of light-line 10 can be shifted alternatively by direct mode Into one in a plurality of memory lines, and/or these alternatively can be displaced in reading out structure.Corresponding memory pipe Reason logic ensures optical charge being respectively stored in free storage line (and these are wiped in advance when necessary), and really Protect and hope order is kept during reading, for example, the order of triggering).This is suitable for itself, specifically, if on semiconductor Memory construction 11 it is smaller than photosensitive surface 10, and therefore, multiple memory cells have space under a photocell.

Specifically, if as foregoing active illumination control result for example prevent generation optical charge (or reduce To possible dark current), then for example by closing the illumination between trigger event, the light between two trigger events can be prevented The collection of optical charge in electric device and spilling.In this case, the difference estimation similar with CDS principles can be contributed to and changed Enter measured value.

Claims

1. a kind of position coder (1), the position coder (1) includes：Position code (9) and optical sensor element, the light At least a portion that sensor element is used to obtain the position code (9) is learned, wherein, the sensor element includes：

The photosensitive line (10) for obtaining area (16), incident photon (p) is converted into electric charge (7) by it,

Reading out structure (12), it is used to export the electric data-signal (22) corresponding with the electric charge (7),

Characterized in that,

The sensor element for electric charge described in interim storage (7) purpose, including

Analog memory structure (11), it is N that it, which has the quantity of the insensitive analog memory unit (14) of light,>The line (13) of 1, Wherein, the quantity of the line (13) of memory cell (14) is more than the quantity of photosensitive acquisition area (16), and

Electric switching construction (15), can be in photosensitive acquisition area (16), the memory list by the electric switching construction (15) Charge transfer is performed between first (14) and the reading out structure (12), and it is realized in such a way, i.e. in memory The charge transfer between the line (13) of unit (14) can be directed to the single line in the memory construction (11) (13) perform or for the subset of the line (13).

2. position coder according to claim 1, it is characterised in that

The quantity of the line (13) of the memory cell (14) is the multiple of the photosensitive quantity for obtaining area (16).

3. position coder according to claim 1, it is characterised in that

The top of the line (13) in the memory construction (11) can be independently of the institute in the memory construction (11) State the lower displacement of line (13).

4. position coder according to claim 1, it is characterised in that

The switching construction (15) is realized in such a way, i.e.

Trigger signal (20) causes to set acquisition time of the position code (9), and by the electric charge (7) from institute The time that photosensitive acquisition area (16) is delivered in the memory construction (11) is stated, and

With the asynchronous read output signal (21) of the trigger signal (20) cause that the defeated of the reading out structure (12) can be set Go out the time.

5. position coder according to claim 4, it is characterised in that

The read output signal (21) is independently in time from the trigger signal (20).

6. the position coder according to claim 1 or 4, it is characterised in that

The sensor element includes

The photosensitive single line (10) for obtaining area (16), and

At least N >=3 bar the line (13) of memory cell (14).

7. position coder according to claim 6, it is characterised in that

The sensor element includes the N >=4 bar line of memory cell (14).

8. position coder according to claim 6, it is characterised in that

The sensor element includes single reading out structure (12).

9. the position coder according to claim 1 or 4, it is characterised in that

The switching construction (15) causes the transmission that the electric charge (7) can be performed between the following

Held between one in the line (10) of photosensitive acquisition area (16) and the line of analog memory unit (14) The transmission of the row electric charge (7),

The transmission of the electric charge (7) is performed between the line (13) of analog memory unit (14), and

Performed between at least one and the reading out structure (12) in the line (13) of analog memory unit (14) The transmission of the electric charge (7),

Wherein, it is at least one second obtain can first obtain with complete it is described first obtain associate first reading between hold OK, second electric charge (7) obtained is temporarily stored in the memory construction (11) in an analog fashion, and it can be in institute After stating the first reading, the time later in being read by least second reads.

10. position coder according to claim 4, it is characterised in that

One in the line of the photosensitive line (10) for obtaining area (16) with the analog memory unit (14) The transmission of the electric charge (7) is pressed between line is performed by the trigger signal (20) the predetermined acquisition time.

11. position coder according to claim 9, it is characterised in that

The transmission of the electric charge (7) can be directed to the simulation between the line (13) of the analog memory unit (14) Activate to each line options in these lines (13) of memory cell (14).

12. position coder according to claim 9, it is characterised in that

The transmission of the electric charge (7) can be directed to analog storage between the line (13) of the analog memory unit (14) The appropriate subset actuating of the line (13) of device unit (14).

13. position coder according to claim 9, it is characterised in that

Between at least one line and the reading out structure (12) in the line (13) of the analog memory unit (14) The transmission of the electric charge (7) is according to the reading letter for being used to read the position code (9) obtained by the acquisition time Number (21) perform.

14. the position coder according to claim 1 or 4, it is characterised in that

The sensor element includes discharging structure (83,42), and it is realized in such a way, i.e. can be present in the mould The electric charge (7) intended in one in memory cell (14) is put before charge transfer is into these memory cells (14) Electricity.

15. position coder according to claim 14, it is characterised in that

It is N bars that the discharging structure (83,42), which can be optionally applied to the quantity of the analog memory structure (11), The subset of line.

16. position coder according to claim 15, it is characterised in that

The discharging structure (83,42) can be selectively used for the single line (13) of the memory construction (11).

17. position coder according to claim 4, it is characterised in that

The memory construction (11) includes memory manager, and it is based on the trigger signal (20) and the read output signal (21) charge transfer is controlled, and it is realized in such a way, i.e.

Based on the read output signal (21), occur to transmit institute based on direction of the analog memory value along the reading out structure (12) The data-signal (22) in the electric charge in memory construction (11), and the output reading out structure (12) is stated, and

Based on the trigger signal (20), it is able to carry out the electric charge (7) being delivered to institute from photosensitive obtain area (16) State in memory construction (11).

18. position coder according to claim 17, it is characterised in that

By the electric charge (7) be delivered in the memory construction (11) near the reading out structure (12) positioning and its In not yet store in the lines (13) of electric charge (7).

19. position coder according to claim 17, it is characterised in that

The output is relative to the triggering asynchronous implement.

20. the position coder according to claim 1 or 4, it is characterised in that

The sensor element is installed using the CMOS on common semiconductor substrate and CCD structures.

21. position coder according to claim 20, it is characterised in that

The memory construction (11) is realized using CCD technologies, and the reading out structure (12) is realized using CMOS technology.

22. the position coder according to claim 1 or 4, it is characterised in that

The sensor element is realized using correlated-double-sampling structure (81).

23. the position coder according to claim 1 or 4, it is characterised in that

The sensor element is realized using correlated-double-sampling structure (81), it is characterised in that is realized from it and is delivered to the reading Line in structure (12), memory construction (11).

24. the position coder according to claim 1 or 4, it is characterised in that

The photosensitive line for obtaining area (16) includes at least one dark pixel (80), and it is protected from incident photon (p) Influence, and wherein, not because of electric charge caused by photon (7), and the electric charge of the dark pixel also passes as dark benchmark in by-line Transmitted during passing.

25. a kind of line by photosensitive acquisition element obtains at least one of method of position code (9), this method come optics Comprise the following steps

Photon is obtained in the acquisition element and the photon is converted into electric charge (7),

The electric data-signal (22) corresponding with the electric charge is exported by read output signal (21) triggering,

It is characterized in that including：

The time of the optics acquisition is triggered by outer triggering signal (20), and according to the triggering, by the electric charge (7) It is delivered to from the photosensitive acquisition element in memory construction (11), the memory construction has analog memory unit (14) N>1 line (13), wherein, the quantity of the line (13) in the memory construction (11) is more than the photosensitive number for obtaining element Amount, and

Before the output by the interim buffer-stored of charge simulation (7) in the memory construction (11), during this period, The transmission of the subset for single line (13) or the line (13) is optionally performed in the memory construction (11),

Wherein, the result as the buffer-stored, the acquisition can be relative to the output asynchronous implements.

26. according to the method for claim 25, it is characterised in that

The quantity of line (13) in the memory construction (11) is the multiple of the photosensitive quantity for obtaining element.

27. according to the method for claim 25, it is characterised in that

The top of the line (13) in the memory construction (11) can be independently of the described of the memory construction (11) The lower displacement of line (13).

28. according to the method for claim 25, it is characterised in that

Using switching construction (15), to perform

Caused by trigger signal (20),

Electric charge (7) is delivered to the described of the analog memory structure (11) from the line (10) of photosensitive acquisition area (16) In one in line

And

Caused by read output signal (21),

Electric charge is delivered to reading out structure from a line in the line (13) in the analog memory structure (11) (12) in, and

Perform from the reading out structure (12) and export the electric data-signal (22).

29. according to the method for claim 28, it is characterised in that

Electric charge is delivered to reading out structure (12) from a line in the line (13) in the analog memory structure (11) In with electric charge (7) acquired in the memory construction (11), buffer-stored at least those lines (13) propulsion carry out.

30. according to the method for claim 28, it is characterised in that

The read output signal (21) can temporally independent mode controls relative to the trigger signal (20).

31. the method according to claim 25 or 28, it is characterised in that

The memory construction (11) manages as by-line shift register.

32. according to the method for claim 31, it is characterised in that

The memory construction (11) manages according to FIFO principle.

33. according to the method for claim 31, it is characterised in that

The subset for the line (13) being able to carry out in memory construction described in selective erasing (11).

34. according to the method for claim 31, it is characterised in that

Before in the line that electric charge (7) is delivered in the line (13), this bar of selective erasing line (13).

35. the method according to claim 25 or 28, it is characterised in that

According to the trigger signal (20), from the photosensitive electric charge (7) for obtaining area (16)

Discharged in discharging structure (83,42), or

It is stored in the analog memory structure (11).

36. according to the method for claim 35, it is characterised in that

The electric charge (7) in the memory construction (11) is passed to not accounting for closest to the reading out structure (12) positioning With in line (13l).

37. the method according to claim 25 or 28, it is characterised in that

Triggered by the trigger signal (20),

The spurious charge previously collected is delivered to First Line in the memory construction (11) from photosensitive acquisition area (16) (13) in, it is used as the rubbish line (tr0, tr1, tr2, tr3) of no code information, then,

The photon (p) for establishing the position code (9) is obtained, and

Acquired electric charge is delivered to the second line (13) in the memory construction (11) from photosensitive obtain area (16) In, it is used as the measurement line (m0, m1, m2, m3) with code information.

38. according to the method for claim 37, it is characterised in that

The electric charge (7) in the rubbish line (tr0, tr1, tr2, tr3) be passed to for electric discharge discharging structure (83, 42) in, and those electric charges in the measurement line (m0, m1, m2, m3) are passed in the reading out structure (12) to export.

39. a kind of position coder (1), the position coder include：Position code (9) and optical sensor element, the optics Sensor element is used at least a portion for obtaining the position code (9), wherein, the sensor element includes：

Reading out structure (12), the reading out structure are used to export the electric data-signal (22) corresponding with the electric charge (7),

Characterized in that,

Electric switching construction (15), can be in photosensitive acquisition area (16), the memory cell (14) and the institute by means of it State and perform charge transfer between reading out structure (12).

40. the position coder according to claim 39, it is characterised in that

The quantity of the line (13) of memory cell (14) is the multiple of the photosensitive quantity for obtaining area (16).

41. a kind of line by photosensitive acquisition element obtains at least one of method of position code (9), this method bag come optics Include following steps

Photon is obtained in the photosensitive acquisition element and the photon is converted into electric charge (7),

Characterized in that,

Triggered by trigger signal (20), the electric charge (7) is delivered to memory construction from the photosensitive acquisition element (11) in, the memory construction has the N of analog memory unit (14)>1 line (13), and

Before the output by the interim buffer-stored of charge simulation (7) in the memory construction (11),